1. Field of the Invention
This invention relates to Time Division Duplex (TDD) wireless communication systems. More particularly, the present invention relates to activation or deactivation of primary and secondary carriers in a Time Division Duplex Long Term Evolution (TDD LTE) system that simultaneously uses multi-carriers via Carrier Aggregation (CA) technology.
2. Description of the Related Art
With the rapid development of wireless communication technology, communication systems have evolved across generations. One of the examples is a Long Term Evolution (LTE) system, which has been developed as a 4th generation LTE system. LTE systems employ a variety of technologies to meet the rapid increase in traffic demand. One such technology that LTE systems use is Carrier Aggregation (CA). Carrier Aggregation refers to a technology that increases the number of carriers used in communication between User Equipment (UE) and an evolved Node B (eNB). For example, Carrier Aggregation increases the number of carriers used from one carrier as disclosed in the related art to a primary carrier and one or more secondary carriers. Such an increase in the number of carriers used in communication between the UE and the eNB increases the amount of transmission by the number of secondary carriers. In LTE technology, a cell in which a primary carrier is served is referred to as a Primary Cell (PCell) and a cell in which a secondary carrier is served is referred to as a Secondary Cell (SCell).
When using Carrier Aggregation, PCell has an additional complexity to control SCell. That is, a determination as to whether to use SCells at a specific PCell may be made, a determination as to conditions for activating and deactivating the SCells may be made, and the conditions for activating and deactivating the SCells may be monitored. After determining the related factors, PCell can control SCells via the factors. A method for activating SCells is also needed. That is, when PCell receives an instruction for activating or deactivating SCells from eNBs, the real operations are required to be specifically described.
Therefore, a need exists for a system and method for performing a self diagnosis of a device without the inconvenience caused when manually selecting a self diagnosis item from a computer or a user interface.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present invention.